8 Best Glock 21 Red Dot Sights

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Today we will be looking at the best Glock 21 red dot sights rich in features to boost the performance of your pistol.

Enhance the performance of your Glock 21 by mounting an effective red dot sight. Reflex sights have revolutionized how we engage with close-range targets. They allow quick target acquisition through their wide field of view and help you land accurate shots every time.

The key to pushing your Glock 21 to its full potential is accessorizing it with the right optics. Red dot sights are by far the most popular optics to use and it is for a good reason.

They are handy for situations that require rapid target finding. Moreover, red dot sights hone the shooter’s accuracy by enabling confident aiming.

What Makes a Great Red Dot Sight for Glock 21?

Mounting a red dot sight on your pistol will help improve your shooting efficiency. To realize the full benefits of a red dot sight, you need to know the features to look for in a red dot sight.

The best red dot sight for pistols is outfitted with a myriad of features that work together to make your shooting more competitive. Firstly, the red dot should have a crisp reticle for accurate and reliable shooting.

The reticle should have adjustable brightness settings that enable easy aiming across a wide range of light conditions. On top of that, the optic should be powered by a long-lasting battery that keeps the reticle optimally illuminated.

The best Glock 21 red dot sights should also come with:

  • Infinite eye relief and parallax-free optics
  • Robust and durable construction
  • Full protection from water, dust, fog, and other elements
  • Multi-coated lenses for fighting glare
  • An easily accessible battery tray

8 Best Glock 21 Red Dot Sights

Below is a list of the best Glock 21 red dot sights worth your consideration. Let’s take a look.

1) SightMark Mini Shot A-Spec M3 Micro Reflex Sight

Best Glock 21 Red Dot Sights

 

 

The SightMark Mini Shot A-Spec M3 is a budget-friendly reflex sight that doesn’t compromise performance. It’s also a versatile and durable red dot sight ideal for home defense and short to medium-range shooting endeavors.

A defining feature of this compact red dot optic is accuracy. It has a crisp and easy-to-use reticle that is accurate in all environments. The reticle is optimally illuminated and powered by an impressive battery with up to 100,000 hours of continuous runtime.

Another facet that makes it one of the best Glock 21 red dot sights is its rugged construction. It is constructed from durable aluminum alloy which is recoil resistant and shockproof. The optic is also IP55 water-resistant, fog-proof, and ideal for use in temperatures ranging from -22℉ to 122℉.

Features

  • Shield RMS-C footprint
  • Durable aluminum alloy
  • IP55 water-resistant rating
  • Low-profile design
  • Red reticle illumination
  • Auto-brightness control reticle
  • Co-witness with standard pistol sights

Pros

  • Long battery life
  • Versatile
  • Mount included
  • Good value for the price
  • Easy to mount and use
  • Easy to zero

Cons

  • Durability issues

2) German Precision Optics SPECTRA Red Dot Sight

Best Glock 21 Red Dot Sights

 

If you want to take your shooting skills a notch higher, you need a top-tier optic like the German Precision Optics SPECTRA Red Dot Sight. It is built for hunting and tactical use in any weather or lighting condition.

The optic is made with magnesium alloy to ensure that it stands the test of time. The robust construction is complemented by a weatherproof design which makes the optic usable even in extreme weather conditions.

Moreover, this red dot optic has GPO bright high-transmission lens coatings responsible for fighting glare. The 3 MOA dot offers the ultimate balance of precision and speed in all light conditions. It also has 6 daytime and 5 nighttime settings that enable confident aiming in any environment.

The other essential features included are infinite eye relief, double HD lens material, and precision 0.5 MOA windage and elevation click adjustments. This feature-rich red dot sight is arguably one of the best Glock 21 red dot sights.

Features

  • 3 MOA red dot reticle
  • LED illumination
  • Waterproof and fog-proof
  • Double HD lens material
  • Unlimited eye relief
  • High-transmission lens coatings
  • Open emitter
  • Magnesium alloy chassis

Pros

  • Night vision compatible
  • Outstanding durability
  • Clear glass
  • Easy to mount

Cons

  • No drawbacks

3) SIG SAUER Romeo 1Pro 1x30mm 6 MOA Red Dot Sight

Best Glock 21 Red Dot Sights

 

 

When it comes to versatility and performance, it is hard to beat the Sig Sauer Romeo 1 Pro 1x30mm red dot sight. You can use it for a wide range of shooting applications at close to medium ranges.

This red dot sight has admirable optical features. Firstly, it has a molded glass aspheric lens that enhances resolution. It also boasts high-performance coatings on the optics to ensure high levels of light transmission.

As outstanding as the optical features are so is its durability. It has an ultra-sturdy aluminum body optimized for use in any environment. The quality construction coupled with the waterproof and dustproof features make the sight ideal for use even in less-than-ideal weather conditions.

This red dot optic also brings to the table a large 6 MOA reticle that comes with 12 adjustable brightness settings. Adapt to different lighting conditions and increase your success in any shooting application.

Superior quality, brilliant optical system, and unrivaled performance make the Romeo 1Pro a force to be reckoned with among the best Glock 21 red dot sights. Create a more efficient shooting solution with the help of a high-performance optic.

Features

  • Fully waterproof and dustproof
  • 6 MOA reticle
  • Molded glass aspheric lens
  • TruHold lockless zeroing system
  • Motion-activated illumination, MOTAC
  • Ruggedized protective steel shroud
  • Aircraft-grade aluminum construction
  • 12 brightness settings

Pros

  • Accurate and reliable
  • Sturdy and well-built
  • Compact and lightweight
  • Crisp clear optics

Cons

  • Fixed power

4) C-MORE RTS2 1x V5 Micro 3 MOA Red Dot Sight

Best Glock 21 Red Dot Sights

 

 

Speedy target acquisition and recovery is what you get from the C-MORE RTS2 1x V5 Micro 3 MOA Red Dot Sight. It has a compact design and lightweight construction that make it easy to install and use.

This red dot optic has a 3 MOA red dot reticle. It is illuminated to create speedy target acquisition in the field. Furthermore, the eye relief is infinite to complement the reticle and boost your glassing comfort.

As one of the best Glock 21 red dot sights, it uses a beam-splitter lens crafted from glass. The lens is hard-coated for maximum light transmission and scratch resistance. On top of that, the red dot sight has a parallax-free design that enables easy shooting from any position.

This red dot sight has a removable battery tray that permits battery change without dismounting it. It also features aircraft-alloy housing and electronics designed to handle recoil and shock.

For the best shooting experience with the Glock 21, mount the V5 red dot sight. The advanced optical system, solid construction, intuitive design and sharp images make the V5 one of the best Glock 21 red dot sights.

Features

  • Matte finish
  • Unlimited eye relief
  • Open emitter
  • 1 MOA adjustment click value
  • V5 hardened electronics
  • 10 brightness settings
  • 3 MOA reticle
  • Removable battery tray
  • Aircraft alloy housing

Pros

  • Lightweight
  • Easy to use
  • Convenient battery access
  • Clear, ultra-bright reticle

Cons

  • None

5) Burris FastFire III Reflex Red Dot Sight

Burris FastFire III Reflex Red Dot Sight

 

 

Burris FastFire III Reflex Red Dot Sight is another compact red dot optic that comes with all the modern features you would expect. It is ideal for hunting, self-defense, and tactical operations at close ranges.

The 3 MOA reticle has three adjustable brightness settings. You can therefore customize it to suit your shooting preference and the ambient lighting conditions. Even better, the optic comes with an automatic light sensor for adjusting the illumination.

When it comes to construction, the optic has an ultra-durable aluminum housing to handle the beating. The chassis has an anodized finish that shields it from scratches and corrosion that causes rust. On top of that, this product is waterproof and fully submersible.

This versatile reflex sight ranks high among the best Glock 21 red dot sights. You can’t go wrong with the Fast Fire III, pair your handgun with this red dot sight for improved performance, accurate shots and quick target acquisition.

Features

  • Waterproof and submersible
  • 3 MOA red dot reticle
  • Black anodized matte finish
  • 90 MOA total windage and elevation adjustment
  • Parallax-free from 10 to 150 yards
  • Aluminum housing
  • Fully-coated optics

Pros

  • Versatile
  • Ease of installation
  • Crisp and accurate reticle
  • Decent value for the price

Cons

  • No night vision-compatible settings

6) Holosun HS507K-X2 1 x 2 MOA Red Dot Sights

Best Glock 21 Red Dot Sights

 

 

Holosun HS507K-X2 has all the features and quality you can find in a top-tier reflex sight and is surely one of the best Glock 21 red dot sights. This red dot sight is engineered for subcompact pistol applications, and it pairs well with most factory iron sights.

The stand-out feature of this red dot sight is its multi-reticle system. It comprises a 2 MOA red dot and a 32 MOA ring. The 32 MOA ring is ideal for long-distance shooting while the 2 MOA aiming dot is best suited for close-range use.

Holosun optics are known for their robust make and this red dot sight is not an exception. It is made with a durable 7075-T6 aluminum housing with a low-glare matte finish. What’s more, it is IP67-rated for use in all weather conditions.

What’s more, the red dot sight has unlimited eye relief that enables shooting with both eyes. It also brings to the table multiple layers of antireflective coatings that fight glare and enhance low-light visibility.

Features

  • Fully waterproof and shockproof
  • 12 brightness settings
  • Multi-coated lenses
  • Lock mode to protect settings
  • Multi-reticle system
  • Parallax-free optical design
  • 1 MOA adjustment per click impact point correction
  • Aluminum alloy housing
  • Durable matte finish

Pros

  • Ease of use
  • Outstanding durability
  • Compatible with night vision gear
  • Convenient battery access

Cons

  • Cheap glass quality

7) Sig Sauer Romeo-X Compact 24mm Red Dot Sight

Sig Sauer Romeo-X Compact 24mm Red Dot Sight

 

 

Sig Sauer Romeo-X Compact 24mm Red Dot Sight is a high-performance optic that comes at a reasonably fair price. It is ideally suited for close-range shooting in nearly all situations.

Its reticle is crisp to ensure accurate shooting and rapid target pick-up. During use, you can adjust the brightness of the reticle in 15 different illumination settings. Even better, three of the lowest settings are compatible with night vision gear.

The construction quality is outstanding. It has a forged aluminum housing for ultimate durability. Furthermore, the distortion-free aspherical lens is impact-resistant to add durability and makes the optic operable in all environments.

Features

  • 5 MOA adjustment click value
  • Low deck height
  • Side-loading battery compartment
  • Motion-activated illumination
  • Enclosed emitter
  • Distortion-free aspherical lens
  • 15 illumination settings

Pros

  • Ease of installation
  • Durable and well-built
  • Clean and crisp optics

Cons

  • Battery life

8) Leupold DeltaPoint Pro 1 x 6 MOA Red Dot Sight

Best Glock 21 Red Dot Sights

 

Here is another rugged optic ideal for Glock 21. The Leupold DeltaPoint Pro Red Dot Sight has a ton of features for speedy acquisition and quick target finding.

It comes with a 2.5 MOA red dot reticle which provides a definitive aiming point no matter the light conditions. The reticle is small, accurate, and ideal for use at a distance. It also features multiple brightness settings for use in a variety of lighting conditions.

The compact size ensures functional handling in the field. In terms of construction, the red dot has a rugged aluminum housing and steel sheath. This construction guarantees reliable performance in any situation.

Another impressive thing about this extremely versatile sight is its optical quality. It uses a professional-grade optical system with stunning optical clarity and detail. Over and above that, it is fully waterproof and fog-proof to withstand extreme weather conditions.

Features

  • 100% waterproof and fog-proof
  • Professional-grade optical system
  • Twilight Red Dot Light management system
  • Unlimited eye relief
  • 5 MOA reticle
  • Motion sensor technology
  • Aluminum alloy construction

Pros

  • Ease of installation
  • Crisp reticle
  • Long battery life
  • Excellent craftsmanship

Cons

  • Bad parallax

Further Reading

Tips for Choosing the Best Glock 21 Red Dot Sights

When probing the market for a reflex sight, there are important considerations to keep in mind to find the best sighting solution for your needs.

Compatibility

Is the red dot sight compatible with your Glock 21? Different red dot sights have different mount systems and the model you pick for your pistol should be compatible. Its installation process should also be quick and straightforward.

Intended Use

It is also important to determine what you intend to use the red dot for. Is it for hunting, self-defense, tactical use, or any other application? Determine the intended use and opt for a red dot that is optimized for that specific activity.

Read: Best Taurus G3C Red Dot Sights

Size and Weight

Glock 21 is an ultra-compact handgun. Its small form factor calls for a red dot sight that is equally compact. The best Glock 21 red dot sights should also have a lightweight construction so it won’t interfere with the precision and performance of the handgun.

Durability

The type of materials used to make a red dot sight determines its overall durability. Lightweight metals such as aircraft-grade aluminum or magnesium alloy are by far the best materials. They are sturdy and duty-worthy yet lightweight. So, opt for a red dot that is made with either.

Read: Best Holosun Pistol Red Dot Sights

Brightness Settings

Red dot sights have adjustable brightness settings that enable easy aiming in all light conditions. Irrespective of the kind of shooting you will be doing, settle for a model that has multiple brightness settings. We recommend at least 8 brightness settings for the best Glock 21 red dot sights.

Battery Life

Red dot sights are powered by batteries. The capacity of the batteries varies from one product to the other. so, be sure to opt for a model that has an extended battery life.

Also, remember to look at the battery placement. For functional handling, we recommend that you go with a red dot that has a side or top-loading battery compartment.

Read: Best Hunting Red Dot Sights

Best Glock 21 Red Dot Sights FAQs

Q: Is it worth Putting a Red Dot on Glock 21?

Yes. It is worth putting a red dot on Glock 21irrespecitve of the activity you use it for. It will enable you to shoot more accurately at a distance. Additionally, you can pursue targets with ease in all lighting conditions.

Q: How Long Do Red Dot Sights Last?

It depends on several factors like the build quality of the red dot and how often you use it. On average, a top-tier model can last up to 5 years with moderate or repeated use.

Conclusion

Getting the most out of your shooting outings comes with having the right tools. All these red dot sights we have mentioned offer the essential features you need to hone your shooting skills in any shooting environment. So, take a look at the key attributes that make each model the right purchase and decide accordingly.